London - Former world heavyweight champion David Haye is 37, has fought just three times in six years, and has an unfortunate knack of picking up injuries in and out of the ring.

Yet the British fighter thinks he should still be in the conversation for world heavyweight titles, that he can "achieve the very best in the division."

Tony Bellew scoffs at that notion.

"David is not back to win world titles, he's back to try to rob the bank," Bellew said on Monday, ahead of his all-British rematch against Haye. "He wants to fight little fatties like me."

Haye certainly looked like a boxer on his way out of the fighting game when he fell through the ropes - bloodied, battered and with only one functioning leg - in an 11th-round loss to Bellew in March 2017.

Known for his impressive physique, athleticism, speed and explosiveness, Haye appeared a spent force that night at the O2 Arena despite being clearly hampered by an Achilles injury sustained in the sixth round. He openly acknowledges underestimating Bellew, a cruiserweight, and thinking he could just turn up and knock him out.

"The last fight was a cracker - everyone enjoyed it, apart from me," Haye said. "I'm going to do what I tried to do last time, but failed miserably."

So, Haye has kept a lower profile this time round. He has dispensed with the trash talk and cheap shots. There have been no punches thrown in news conferences like in November 2016

"Last time round I was a bit angry," Haye said, "this time round not so much."

Haye said he has never been in better shape, that his bodily feels "eerily nice" - like a car having a major service, with "new tires, new clutch, oil change, it's had everything revamped."

The proof will come back at the O2 on Saturday, when he tries to avenge the third loss of his 31-fight professional career.

"For the first time in your career, you are fighting for your career," the 35-year-old Bellew said at a news conference in his home city of Liverpool. "If this goes wrong, nothing can save you. I've done this five or six times. I know the kind of pressure it brings. You're in a lot of trouble on Saturday."

The original date for the rematch was December 17, but it was postponed after Haye sustained an injury to his bicep falling down some stairs while doing a conditioning exercise.